Dairy contributions to environmental impacts and nutritional supplies in United States agriculture

With a growing demand for nutrients worldwide, changes must be made to our food production system in order to properly feed the growing global human population. Increasing media attention is devoted to the possibility of removing animals from agriculture to reduce the environmental impact of food production. In this work, the effects of removing dairy products from the United States agricultural system are explored. Three scenarios were simulated: (1) depopulation (DEP), where cows would be slaughtered and land would be used for human consumable crops; (2) current management (CM), where cows would be retained, but all products would be exported or used for non-human consumption purposes; and (3) retirement (RET), where cows are retired to pasture land at a population suitable for the land mass. We anticipate that the general public would favor CM and RET scenarios because they preserve animals' lives. However, under RET, we expect a 27.8% decline in dairy-related GHG emissions, accounting for only about 5.5% of total agricultural GHG emissions. Under all 3 scenarios, a-linoleic acid, calcium, vitamin A, vitamin D, vitamin B12, riboflavin, choline, and 11 other micronutrients all decreased in nutrient supply by more than 20% when compared to the current agricultural system. The only time these nutrients could be met was specific cropping strategies within a land-allocation scenario. This research shows that a possible unintended consequence of the removal of dairy animals from the food production system would be increased deficiencies in essential nutrients and that the magnitude of GHG declines would likely be proportionally less than animal decline.